Department of Environmental Science and Engineering, Indian Institute of Technology Bombay, Mumbai, Maharashtra, India.
Waste Manag Res. 2024 Jan;42(1):51-58. doi: 10.1177/0734242X231171044. Epub 2023 May 21.
Anaerobic digestion (AD) is a prominent treatment method for the sludge produced from sewage treatment plants. Poor solid reduction and longer retention time are the main drawbacks of AD. Thermal hydrolysis (TH) is a potential pretreatment method for solubilization of sewage sludge (SS) solids thereby improving biogas production during AD post-treatment. In this study, the SS sample (total solids = 1.75 wt% and total chemical oxygen demand (COD) = 15,450 mg L) was subjected to TH pretreatment (temperature = 140-180°C and reaction time = 60 minutes) in a 0.7-L capacity stainless-steel high-pressure reactor. At a reaction temperature of 180°C, the maximum solid solubilization (total dissolved solids = 4652 mg L) and improved dewaterability (time to filter = 4.7 s.L g) were observed. The biochemical methane potential test results showed almost doubling of methane generation from 145 to 284 mL gCOD after TH pretreatment at 180°C. The life cycle assessment approach was used to compare various SS treatment and disposal scenarios, two of which included hydrothermal pretreatment. The scenarios involving hydrothermal pretreatments showed the least global warming potential.
厌氧消化（AD）是污水处理厂产生的污泥的主要处理方法。固体减少率低和停留时间长是 AD 的主要缺点。热水解（TH）是一种潜在的预处理方法，可使污水污泥（SS）固体溶解，从而提高 AD 后处理过程中的沼气产量。在这项研究中，SS 样品（总固体=1.75wt%，总化学需氧量（COD）=15450mg/L）在 0.7L 容量的不锈钢高压反应器中进行 TH 预处理（温度=140-180°C，反应时间=60 分钟）。在 180°C 的反应温度下，观察到最大的固体溶解（总溶解固体=4652mg/L）和改善的脱水性能（过滤时间=4.7s·L/g）。生物甲烷潜力测试结果表明，在 180°C 下进行 TH 预处理后，甲烷生成量从 145 增加到 284mL/gCOD，几乎增加了一倍。生命周期评估方法用于比较各种 SS 处理和处置方案，其中两个方案包括热液预处理。涉及热液预处理的方案显示出最小的全球变暖潜力。
